A Novel Alternating Cell Directions Implicit Method for the Solution of Incompressible Navier Stokes Equations on Unstructured Grids

Download

10.18869-acadpub.jafm.73.243.27654.pdf

Date

2017-01-01

Author

Bas, O.
ÇETE, ALİ RUHŞEN
Mengi, S.
Tuncer, İsmail Hakkı
Kaynak, U.

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

232
views

138
downloads

In this paper, A Novel Alternating Cell Direction Implicit Method (ACDI) is researched which allows implementation of fast line implicit methods on quadrilateral unstructured meshes. In ACDI method, designated alternating cell directions are taken along a series of contiguous cells within the unstructured grid domain and used as implicit lines similar to Line Gauss Seidel Method (LGS). ACDI method applied earlier for the solution of potential flows is extended for the solution of the incompressible Navier-Stokes equations on unstructured grids. The system of equations is solved by using the Symmetric Line Gauss-Seidel (SGS) method along the alternating cell directions. Laminar flow fields over a single element NACA-0008 airfoil are computed by using structured and unstructured quadrilateral grids, and inviscid Euler flow solutions are given for the NACA-23012b multielement airfoil. The predictive capability of the method is validated against the data taken from the experimental or the other numerical studies and the efficiency of the ACDI method is compared with the implicit Point Gauss Seidel (PGS) method. In the selected validation cases, the results show that a reduction in total computation between 18% and 23% is achieved by the ACDI method over the PGS. In general, the results show that the ACDI method is a fast, efficient, robust and versatile method that can handle complicated unstructured grid cases with equal ease as with the structured grids.

Subject Keywords

Alternating cell directions implicit method, ACDI, U-MUSCL, Artificial compressibility, Incompressible N-S solver

URI

https://hdl.handle.net/11511/35070

Journal

JOURNAL OF APPLIED FLUID MECHANICS

DOI

https://doi.org/10.18869/acadpub.jafm.73.243.27654

Collections

Department of Aerospace Engineering, Article

Suggestions

OpenMETU
Core

A frequency domain nonparametric identification method for nonlinear structures: Describing surface method Karaagacli, Taylan; Özgüven, Hasan Nevzat (Elsevier BV, 2020-10-01) In this paper a new method called 'Describing Surface Method' (DSM) is developed for nonparametric identification of a localized nonlinearity in structural dynamics. The method makes use of the Nonlinearity Matrix concept developed in the past by using classical describing function theory, which assumes that nonlinearity depends mainly on the response amplitude and frequency dependence is negligible for almost all of the standard nonlinear elements. However, this may not always be the case for complex nonli...
A new modal superposition method for nonlinear vibration analysis of structures using hybrid mode shapes Ferhatoglu, Erhan; Ciğeroğlu, Ender; Özgüven, Hasan Nevzat (Elsevier BV, 2018-07-01) In this paper, a new modal superposition method based on a hybrid mode shape concept is developed for the determination of steady state vibration response of nonlinear structures. The method is developed specifically for systems having nonlinearities where the stiffness of the system may take different limiting values. Stiffness variation of these nonlinear systems enables one to define different linear systems corresponding to each value of the limiting equivalent stiffness. Moreover, the response of the n...
An octree-based solution-adaptive Cartesian grid generator and Euler solver for the simulation of three-dimensional inviscid compressible flows Kara, Emre; KUTLAR, AHMET İHSAN; Aksel, Mehmet Haluk (2016-01-01) Cartesian grid generation methods are especially designed algorithms to generate automatic grids for complex geometries and to simulate flows around such geometries regardless of the body shape. Cartesian grids are generated by constructing an octree-based data structure for the purpose of connecting the Cartesian cells to each other. Entire algorithm is implemented in object-oriented FORTRAN programming language. Some special Cartesian algorithms, namely, Ray-Casting method and cut-cell adaptation are used...
A unified approach for the formulation of interaction problems by the boundary element method Mengi, Y; Argeso, H (Wiley, 2006-04-30) A unified formulation is presented, based on boundary element method, in a form suitable for performing the interaction analyses by substructure method for solid-solid and soil-structure problems. The proposed formulation permits the evaluation of all the elements of impedance and input motion matrices simultaneously at a single step in terms of system matrices of the boundary element method without solving any special problem, such as, unit displacement or load problem, as required in conventional methods....
A Novel Computational Method to Calculate Nonlinear Normal Modes of Complex Structures Samandarı, Hamed; Ciğeroğlu, Ender (2019-01-31) In this study, a simple and efficient computational approach to obtain nonlinear normal modes (NNMs) of nonlinear structures is presented. Describing function method (DFM) is used to capture the nonlinear internal forces under periodic motion. DFM has the advantage of expressing the nonlinear internal force as a nonlinear stiffness matrix multiplied by a displacement vector, where the off-diagonal terms of the nonlinear stiffness matrix can provide a comprehensive knowledge about the coupling between the mo...

Citation Formats

O. Bas, A. R. ÇETE, S. Mengi, İ. H. Tuncer, and U. Kaynak, “A Novel Alternating Cell Directions Implicit Method for the Solution of Incompressible Navier Stokes Equations on Unstructured Grids,” JOURNAL OF APPLIED FLUID MECHANICS, pp. 1561–1570, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35070.